Moving the start/end of systems is extremely slow

I use a kind of proportional notation in my music which often means every system can have a different length. In the note spacing tool of engrave mode, the percentages and precise staff-length measurements are very helpful. However, I find that, even in very simple and sparse flows (the one I’m currently working on has a grand total of 5 notes), each millimeter of staff shortening takes about 3 seconds to process, and, because this can only be done with the keyboard, to move the staff to, say, the middle of the page, takes more than a minute, and very often I overshoot the mark in my haste to push the arrow key 80 times or so and then have to backtrack.
I would very much like a feature where I could click on the box of data to the right of the staff (where the percentages and length of the staff are) and just choose the staff length or percentage of musical data/staff length and the staff would jump to the correct position. (That, or the extreme amount of processing which mysteriously slows this operation down would somehow be limited.)

Given that I can’t find any other thread on this topic I might be the only one who uses engrave mode in this way, so I recognise it’s an extremely niche feature request, but it does bother me with literally every score, so I’m (finally) putting it out there…

Thanks!

Which key combination are you using to move the right-hand end of the system?
I’m on a Mac, so the cmd key would probably be the ctrl key if you’re on Windows (and opt is the alt key).
Opt-arrow moves the smallest distance with one press. Shift-opt-arrow moves more. Cmd-opt-arrow moves even more.

Another thing to consider, but which could cause more problems than it solves:
Dragging the right-hand edge of a frame with the mouse is possible and is a lot quicker than using keystrokes. If each system was in a separate frame, this would be much quicker than moving the end of the system. As I have not yet had a need to experiment with using frame arrangements other than Dorico’s defaults, I really don’t know if there would be any weird behaviours and unexpected happenings with multiple music frames on each page. I imagine that the frames would have to be set up before inputting any notes, but I have had no experience (yet) of implementing what I have just described. Other users might, and they would be in a much better position to offer useful advice.

Thanks for the response.
I’m on a Mac and using Cmd-opt-arrow, which moves 1mm at a time. When wishing, for example, to move 8 cm, that’s a lot of keystrokes, and it’s a lot of waiting in between each keystroke while Dorico recalculates spacing (despite there being minimal material to think about).
I have used the trick of putting each system in a separate frame (which, as you say, can be resized with ease), but that also takes a lot of time to set up, and has the demerit of losing out on the automatic vertical spacing of the systems which I generally do want to keep.
In the end, I don’t think this is a problem to be solved within the current Dorico; it’s more of a feature request for future editions regarding being able to specify the percentages and/or lengths of systems in engrave mode.

If dragging the edge of the system with the mouse is not likely to be implemented, it would be handy to have another key combination which would move a selected item by an even greater distance, and maybe a means of customising that distance. Also, the ability to set the position of the end of the system using the Properties panel with (while I’m daydreaming) a grid overlay as a visual aid when judging how far to move.

Yes, this would be great (and probably more in keeping with the overall design philosophy of Dorico than my suggestion of being able to click the box with the percentages (to the right of the system) and adjust from there).

We know that not being able to move the start or end of a system except by way of a key command is not ideal, and we do hope to provide further means of doing this in future.

That’s great to hear! Thanks